You can change jobs if you need to, but it’s best to stay with the same employer if you can. When you change jobs, you break your apprenticeship contract. Even though you can continue your apprenticeship with a new employer, it can take a few months before you sign the new contract. So by staying with one employer for your whole apprenticeship, you’re more likely to finish on time.
If you do need to change jobs along the way, make sure your new employer is happy to offer you an apprenticeship. Any work you’ve already had signed off will still count, so you can continue from where you left off once you sign your new contract.